Effect of Surface and Subsurface Drip Irrigation Systems on Yield of Cotton in Orzoueyeh, Kerman Province

Application of the modern irrigation systems such as T-Tape irrigation system is one of the ways to achieve aptimal irrigation The present study deals with the effect of surface and subsurface drip irrigation systems on the cotton yield For this purpose، a field experiment was conducted in the Agricultural and Natural Resource Research Institute of Orzoueyeh، located in the Kerman province. The experiments were conducted in a split plot design based on the Randomized Complete Block Design (RCBD) with three replications. The treatments were comprised of three levels of the crop water requirements (i. e. irrigation based on 100، 80 and 60 percent of crop water requirement) in main plot and with the two irrigation systems، surface one and subsurface one. The results showed that the yield resulting from treatments with 60 and 80 percent crop water requirement was respectively 981 and 413 kg/ha lower than that of treatment with 100 percent crop water requirement. In addition، the obtained yield due to subsurface system was 248 kg/ha greater than that of the surface pattern. The interaction of treatments on the yield of the crop also indicates that the treatment with subsurface system and 100 percent crop water requirement produces the maximum yield. Despite equal water consumption in each sub plots، the WUE in subsurface system was 14 percent higher than that of surface system. From the economical point of view، benefit to cost ratio in the subsurface system is 8 percent less than surface system. Considering the results obtained in this study in the light of water saving as the main objective in deficit irrigation and water use efficiency (WUE) for cotton cultivation in Orzoueyeh، the 80% of crop water requirement is preferred